Multiple-arc welding



O. A. KENYON.

MULTIPLE ARC WELDING.

APPLICATION FILED HOV- I9, ma. RENEWED mu. 2. 1920.

1,340,056, Pawnmd May 11, 1920.

HELD/N6 LINE b67150)": 0229A Iago York city in the county of New UNITED STATES PATENT goriuon.

OTIS ALLEN KENYOLL'OF NEW YORK, H. Y.

MULTIPLE-Am WELDING.

To all whom it may concern:

Be it known that I, OTIS A. KENYoN, a citizen of the United States, residin at New ork and State of ew York, have invented certain new and useful Im rovements in Multiple- Arc. Welding, 'of w ich the following is a specification.

My invention relates to certain new and useful improvements in electric arc weldin and particularly to a system of arc wcfiding which employs a gluralit of individually controlled wel ing e ectrodes adapted to operate simultaneously on the same weld, and where means are provided for maintaining a constant len h of are between each individual electro e and the weld, andmy invention consists of the parts andthe arrangements and combinations of partswhich I will hereinafter describe and set forthfin the claims.

Inthe accompanying drawings forming part of this specification, and in which similar reference characters indicate like parts in the several views;

Figure 1 illustrates more or less diagrammatically one embodiment of my invention;

Fig. 2 illustrates diagrammatically the method of depositing the metal;

Fig. 3 illustrates a modification showing the arrangement of three electrodes.

Fig. 4 illustrates the electrode feeding mechanism.

In metallic arc welding, if highest quality work is to be obtained the arc must c'ome into actual contact with the surfacesto be fused. Unless the are does touch every part of the surfaces to be fused, metal from the electrode will run into the joint and simply chill where it strikes the surface without fusin in.

In and welding, the expert operator manipulates the electrode in such a way as to cause the arc to travel over every art of the adjacent surfaces of the joint. his action is called weaving. V

This weaving action is not a sim le oscillating motion. Starting on one si e of the joint the operator draws the are along one edge, backs u slightly on the same edge, crosses on t e newly deposited metal; travels forward on the other edge, backs up and crosses, and then repeats the whole operation indefinitely until the weld is completed. In this manner the operator fuses both sides of the joint and joins up the two Bpecmcatien 0! Letter! mam. P t t May 1920 Application fled November 19, 1918, Serial 110. 268,190. Renewed January 2, 1850. Serial No. 849,688.

sides with the metal that runs off the end of the electrode.

It is not necessary to .weave in all weldrug-operations. For instance, when weldmg thm sheet, if the edges to be. joined are close together so that the are can touch both at the same time, then the electrode can be advanced in a perfect line along the weld. On the other hand, where the parts to be joined are thicker or are not close together, i

application of automatically-fed electrodes to joints where strai ht-line welding is not satisfactory. Hereto ore, it has been necessary to provide some more or less compli-' cated' mechanism to carry the electrode .throu h the proper motions. vI avoid the use 0 I any complicated mechanism by employing more thanone are on the same. joint at the same time, 'each one traveling in a straight line and all being so arranged that the whole surface to be welded WlllOOIIlG into actual contact with an are at every point.

It might beflpossible tooperate these arcs in multiple 0 less resistance was used in each arc circuit, there would be a pronounced tendency for pumping between the arcs to occur. The best way to accomplish the result would be to feed each are from a separate generator.

the same machine, but un- However, when not more than two arcs were necessar the series system covered b my former atent No. 1,181,227, dated M ay 2, 1916, could be used advanta ously. In the present instance I assume th: use of the series system to explain the operation of the method.

In the'said drawings, Fig. 1, A and B are electrode feeding devices; 1 and 2 are suit able controllin mechanisms; D, D, are driving rolls; P are electrodes; 1', r are guide rollers for the electrodes; W, W are parts to be welded; X is the main welding line circuit; 6, b g, g, are appropriate contactors; c, c are coils; h, h are springs lot connected to the contactors; k, k are resistors; j, j and Z, Z are contact keys; and z, 'i' are rheostats.

In the arrangement described and shown in Fig. 1, the control'of the arcs is accomplished by the controllers, 1 and 2 which ma be of any desired construction and which operate as follows:

The main welding line circu t is shown at X and it carries the welding current which is supplied from a constant current generator, as will be understood by those skilled in this art. The arcs are shown 1n operation, in which condition the contactors, b and g are open, said contactor, I), being held open by the coil 0, which carries the current to the arc, and the contactor, g, being held open by the spring, b the coil on the said contactor, 9, being excited by the constant-potential line EX through the resistor, is, of suitable construction and the value of which is so chosen that the current through the coil, e, is SllfilClBIlt to hold the contactor closed, but not sufiicient to close it. When it is desired to stop welding, the contact making switch or key, 1, is closed, thus cutting out the allowing suflicient current throu h the co 1l, e, to close the contactor, g, whic s ort-circuits the arc allowing -the current to pass directly to the other side through the line X and Y, and thence through the electrode, P, and the controller, 2, to the line X. As soon as an arc closes the contactor, b. In order to start the are again the operator presses the contact key, j, which cuts off the current from the coil, e, which operation allows the spring, h, to open the contactor, g, and leave the resistor, a, in the circuit, and the drop across this resistor furnishes sufiioient voltage to start the arc, The first current through the arc passes through the coil, 0, and opens the contactor, 6, thereby leaving the are alone in the line.

The mechanism described is shown at the left of Fig. 1, but a corresponding, arran ement is shown at the ri ht of Fig. 1, by t e controller, 2, and it Wll be understood that this controlling mechanism controls the secend are and operates in exactly the same way as described for the control er, 1. The result is that each arc is absolutely independent of the other.

In the arrangement shown in 1 1g. 1, the length of the arc is maintained biga groper control of the feeding rollers, by means of mechanism, say substantially as shown in Fig. 4, but in case the feed 1s not right or that for any other reason the arc becomes too long the len th ofsaid arc can be kept within a given imit by adjustin the rheostat, i, in'series w th a 0011, f, who is connected across the arc. The passage of the proper amount of current through said resistor, k, anddies out, the spring d,

coil, f, when there is a normal value of current in the coil e, willclose the contactor, g, thus cutti the are out of the circuit.

In Fig. 2 show diagrammatically the method of de ositing the metal and it will be understoo that when the series connection of arcs is used, one of the arcs must be connected with the electrode on the negative s de of the circuit and the other on the positive side. Since the positive side of the arc generates about three times as much heat as the negative side, one of these arcs will generate more heat in the electrode than the other; therefore if the same'current is used in both the positive electrode will melt faster than the ne ative one. On this account it is desirab e to place the negative electrode a little in advance of the positive one so that the joint will be hotter under the positive electrode and thus tend to equalize the unbalance in temperature. I am permitted to adjust an remaining unbalance by shunting the positive electrode arc with a resistance.

Another factor that enters into the operation of two arcs on the same piece at the same time and in close proximity to each other is the electro-ma etic action. \Vith the positive and negative electrodes the arcs will repulse each other, while with two arcs of the same polarity there would be an attractive action both of which would tend to make the arcs travel around. This interaction of the arcs would assist in making a successful joint as it would keep the arcs from following a perfectly straight line. They would be constantly shift ng their position on account of the magnetic action of the current, and thus cause the arcs to play over' a larger area than would be covered by operating with each are 0 crating independently and at considerab e distance from one another.

In the arran ment shown more or less diagrammatical y in Fig. 3, I employ three electrodes. In his case each electrode is connected with t e same polarity on the arc and the current adjustment is obtained by means of the ballast resistances, c, c c, which also serve to prevent surging of current between the ares. In the same way I might connect any desired number of arcs of either or both polarities to the same piece of work, the num er depending only on the size of the joint.

From this description it wilLbe understood that the present invention has partic-.ular relation to the agplication of automatically feeding electro es to points where straiglht line wel ing is not satisfactory, and that employ a simplemechanism which includes a urality of individually controlled weldmg electrodes which are adapted to operate simultaneously on the same weld, each are traveling in a straight line and all being so arran d that the whole surface to bewelded Wll come into actual contact with an are at every oint.

Having thus described my IIIYGIltlOIl what I claim as new and desire to secure by Letters Patent is 7 1. In automatic electric arc welding, a plurality of individually controlled weldmg electrodes adapted to operate simultaneously on the same portion of weld.

2. In automatic electric arc weldin individuall controlled welding electrofes in series, a apted to operate simultaneously on the same portion of weld.

3. In automatic electric arc welding, a

plurality of welding electrodes adapted to operate simultaneously on the same portion 0 weld, and means for maintainin a constant length of are between each in ividual electrode and the weld.

In automatic electric arc weldin a plurality of welding electrodes adapteg to operate simultaneously on the same portion of weld, and means controlled by the voltage across each individual arc to maintain a constant length of arcs between the electrodes and the weld.

In testimony whereof I aflix my signature.

OTIS ALLEN KENYON. 

